<!DOCTYPE html>
<html>
    <head>
        <style>
            #container {
                position: absolute;
                left: 100px;
                top: 100px;
                width: 467px;
                height: 462px;
                background-color: rgb(128, 128, 128);
            }
            .rect {
                position: absolute;
                mix-blend-mode: difference;
            }
            #pink {
                left: 80px;
                top: 60px;
                width: 250px;
                height: 250px;
                background-color: rgb(128, 128, 0);
            }
            #blue {
                left: 140px;
                top: 120px;
                width: 250px;
                height: 250px;
                background-color: rgb(0, 128, 128);
            }
            #turquoise {
                left: 180px;
                top: 180px;
                width: 250px;
                height: 250px;
                background-color: rgb(128, 0, 128);
            }
        </style>
    </head>
    <body>
        <div id="container">
            <div id="pink" class="rect"></div>
            <div id="blue" class="rect"></div>
            <div id="turquoise" class="rect"></div>
        </div>
    </body>
</html>
